(a) Technical Field
The present invention relates to a method and apparatus for manufacturing a melt-blown fabric web. More particularly, the present invention relates to a method and apparatus for manufacturing a melt-blown fabric web having improved filament cohesion and bulkiness.
(b) Background Art
Generally, a process of manufacturing a melt-blown fabric web includes a wave forming process in which a thermoplastic resin, such as polypropylene resin, is injected in a perpendicular and downward direction to from filaments. This process lengthens the filaments and provides them in a waveform. In a fabric web forming process, the wave-form filaments are collected and deposited to form a fabric web.
Melt-blown fabric webs composed of microfilaments have been widely used for various types of high-performance filters, wipers, oil absorbents, insulating materials, sound-absorbing materials, and so forth.
Various types of microfiber sound-absorbing materials formed from melt-blown fabric webs have been described. For example, U.S. Pat. No. 3,016,599 describes a fabric web which contains staple fibers of 1 denier in average diameter provided at 25-70 wt % in a micro fiber. U.S. Pat. No. 4,041,203 describes a melt-blown fabric web in which filaments aligned with molecularities of 10 μm and 12 μm are intermittently coupled by means of heat and pressure. U.S. Pat. No. 4,118,531 describes a fabric web having a compression elasticity of at least 30 cm3/g, which is formed of micro fibers and crimped fibers at a ratio of 9:1 or 1:9.
In addition, U.S. Pat. No. 5,841,081 describes a three-dimensional (3D) nonwoven web sound-absorbing material manufactured through a melt-blown processing using a microfiber. U.S. Pat. No. 5,993,943 describes a method for improving rigidity by spinning a melt-blown fiber and passing the fibers through a series of heating chambers to align the melt-blown fibers, and an aligned fiber having no shot manufactured by the method. U.S. Publication No. 2004-0097155 describes a fabric web which is a nonwoven fabric web having no macro pores, which includes 5 wt % or more of a C-shaped staple fiber.
Korean Patent Application Publication No. 2005-0093950, entitled “Wallpaper for Automobile and Manufacturing Method”, describes a wallpaper for an automobile in which a nonwoven layer, which contains an amount hollow fiber in the nonwoven fabric formed of a general fiber material, and a heterogeneous cross-section fiber layer are bound and deformed into a spring form. Korean Patent Application Publication No. 2007-0118731, entitled “Sound-Absorbing Material”, describes a sound-absorbing material containing a nano-fiber nonwoven fabric composed of a nano fiber of 1,000 nm or less in average diameter.
In addition, Korean Patent Application Publication No. 2008-0055929, entitled “Multi-Layer Product Having Sound-Absorbing Property, and Manufacturing Method and Using Method Thereof”, describes a multi-layer product having a sound-absorbing property, which includes a support layer and a submicron fiber layer formed thereon, which is composed of a polymer fiber of 1 μm or less in diameter.
In particular, in the field of sound-absorbing materials, melt-blown fabric webs composed of only a microfiber of a single component (i.e., a polypropylene microfiber 100% form), and a fabric web composed of a microfiber and a staple fiber, which have chemically different components (e.g., in a form in which a melt-blown microfiber of a polypropylene material is mixed with a staple fiber of a polyethyleneterephthalate material of 4-8 deniers), are most widely used.
However, a conventional melt-blown microfiber sound-absorbing material, (e.g., a sound-absorbing material composed of a single-component microfiber produced by a conventional melt-blown production method) fails to provide sufficient sound-absorbing performance, has low cohesion strength between the microfibers, and has a specific fiber directivity in the fabric web. Moreover, in the case of a microfiber sound-absorbing material composed of microfibers and heterogeneous staple fibers, scraps generated during production and usage are not usable and are entirely discarded. Thus, this process is not eco-friendly, and when the scraps are discarded, environmental contaminants may be generated, such as large amounts of carbon dioxide.